1. Field of the Invention
The present invention relates to a memory device utilizing semiconductor properties and a method for manufacturing the memory device.
2. Description of the Related Art
A typical example of a widely used memory device is dynamic random access memory (DRAM), which is composed of one capacitor and one transistor (also referred to as cell transistor).
A planar transistor has been conventionally used to form a DRAM. More recently, a method using a recessed channel array transistor (RCAT) in which a gate is arranged three-dimensionally so as to prevent leakage current due to a short-channel effect is employed because of miniaturization of circuits (see Non-Patent Document 1).